1. Field of the Invention
The present invention relates to an image recording apparatus and a method of adjusting a recording head in an image recording apparatus, more particularly to technology for adjusting a recording timing of a recording head and a position to attach the recording head.
2. Description of the Related Art
For an image recording apparatus with a recording head in which a plurality of nozzles for ejecting ink are arranged, there have been proposed many technologies for correcting an attachment position to attach the recording head, in order to prevent uneven printing that is caused by the displacement of the attachment position of the recording head when the image recording apparatus is vibrated upon transportation thereof or when the recording head is replaced.
Japanese Patent Application Publication No. 07-323582, for example, discloses an image forming apparatus based on an inkjet recording system that forms images by using a plurality of recording heads. The image forming apparatus has: a replacement detection means for detecting that at least one of the recording heads is replaced; a printing means for printing parallel two patterns by using a standard head and another head out of the recording heads when the replacement of the recording head was detected by the replacement detection means; a reading means for reading the parallel two patterns printed by the printing means; a position calculation means for calculating a position of a center dot on each of the patterns read by the reading means; and a displacement calculation means for calculating, from the position of the center dot on each pattern calculated by the position calculation means, a width between the patterns made by the standard head and a width between the patterns made by the standard head and the other head, and calculating an amount of displacement of the recording heads based on a difference between the widths.
This technology can accurately evaluate the displacement between the recording heads caused by replacing and attaching the recording heads, as well as the displacement caused by reciprocating printing. However, it is disadvantageous in that if the standard head has been displaced, the replaced heads are similarly displaced since the amount of displacement is calculated with respect to the standard head. An additional problem is that, when replacing all of the recording heads, there is no standard head to apply.